Malcolm Dole

By means of electrospraying a dilute polymer solution into an evaporation chamber, negative macroions can be produced and a molecular beam formed by sampling the gaseous mixture of macroions, solvent, and nitrogen molecules with a nozzle-skimmer system of the Kantrowitz–Gray type. The macroion current can be detected by a Faraday cage after the light ions have been repelled from the beam by negative voltages on a repeller grid. Theoretical repeller voltages which best agree with the observed are those calculated by assuming a macroion velocity within 2% of the estimated supersonic beam velocity of 743 m sec−1. Polystyrene macroions of 51 000 weight-average amu tend to form dimers and trimers in the beam while larger polystyrene macroions of 411 000 weight-average amu appear mostly to be multiply charged single species. The results demonstrate that definite mass/charge states can be formed by the electrospray technique, that a considerable monochromatization of macroion velocities in the beam takes place, and that the macroions become highly concentrated relative to low-molecular-weight solvent and nitrogen ions during the transit time in the supersonic beam.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTHE VISCOSITY OF AQUEOUS SOLUTIONS OF STRONG ELECTROLYTES WITH SPECIAL REFERENCE TO BARIUM CHLORIDEGrinnell Jones and Malcolm DoleCite this: J. Am. Chem. Soc. 1929, 51, 10, 2950–2964Publication Date (Print):October 1, 1929Publication History Published online1 May 2002Published inissue 1 October 1929https://pubs.acs.org/doi/10.1021/ja01385a012https://doi.org/10.1021/ja01385a012research-articleACS PublicationsRequest reuse permissionsArticle Views2687Altmetric-Citations1129LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Hairless albino mice with squamous cell carcinoma were exposed to a mixture of 2.5 percent oxygen and 97.5 percent hydrogen at a total pressure of 8 atmospheres for periods up to 2 weeks in order to see if a free radical decay catalyzer, such as hydrogen, would cause a regression of the skin tumors. Marked aggression of the tumors was found, leading to the possibility that hyperbaric hydrogen therapy might also prove to be of significance in the treatment of other types of cancer.

Abstract Specific heat measurements have been carried out on granular and annealed Marlex 50, a polyethylene polymerized at relatively low pressures, over the temperature range −25 to 150°C. Calculation of the crystallinity yields maximum values of 82.6 and 93.8% for the granular and annealed Marlex 50, respectively. The specific heat of crystalline Marlex 50 at room temperature is slightly less than that previously predicted for a crystalline paraffinic hydrocarbon of infinite chain length. The maximum melting temperature, 134.8°, is about 1.7° less than that of polymethylene and close to the predicted value for a long chain solid hydrocarbon. 90% of the solid Marlex 50 melts over a 15° range of temperature. The shape of the specific heat‐temperature curve can be well reproduced by application of Flory's theory of crystallization in copolymers by considering branch points and chain ends to be the noncrystallizing copolymer units. Negative temperature drifts just below the melting point and low specific heat values just above have not been explained.